Attachment plug



Feb. 18, 1941. J L Y ATTACHMENT PLUG Filed June 20, 1938 Z. 1 v 8 w mm mm W 6 6 m of 0% 5 1 Patented Feb. 18, 1941 UNITED STATES ATTACHMENT PLUG Lewis J. Clayton, Toronto, Ontario, Canada, as-

signor to Viceroy Manufacturing Company Limited, Toronto, Ontario, Canada Application June 20,

2 Claims.

The principal objects of this invention are to provide an attachment plug of the pronged type which may be manufactured at low cost by a simple moulding operation and in which the 5 prongs will be inserted and flexibly retained in position in an effective manner and in which the lead-in wires may be effectively anchored in a simple manner to the prong terminals.

A further and important object is to provide an attachment plug which will not be injured or broken or rendered otherwise unsuitable for service should the same be trod upon or subjected to shock. The principal features of the invention reside in the moulded formation of a flattened resilient plug body with terminal receiving sockets and co-operating supporting surfaces and in the provision of pronged terminals specially formed to physically interlock with the walls of the socket and to engage the supporting surfaces in positioning contact.

In the drawing, Figure 1 is a side elevational view partly in section of an attachment plug constructed in accordance with the present invention.

Figure 2 is an edge elevational view.

Figure 3 is a terminal end view.

Figure 4 is a mid-sectional side elevation of the moulded plug body.

Figure 5 is a transverse sectional elevation taken on the line 55 of Figure 4.

Figure 6 is an end view of the moulded plug body prior to insertion of the pronged terminals.

Figures '7 and 8 are edge and side elevational views respectively of the insertable pronged terminals illustrating the special formation thereof for co-operation with the plug body.

It is very desirable from a standpoint of service as well as safety to provide an attachment plug for appliances which will be of a resilient nature and not likely to fracture readily and to also provide for the moulding of the plug body separately from the terminals and to provide for the subsequent insertion of the terminals and retention thereof in the plug body and while various attempts have been made along this line, difficulty has been experienced either in the assembly of the terminals or the adequate anchoring thereof in the plug body due to inaccurate positioning of the terminals and likelihood of their becoming dislodged from their proper relation to the plug body and the present invention has been devised to overcome these difliculties. Y

In the preferred form of construction shown,

1938, Serial Nb. 214,710

(Cl. ire-s61) the plug body I is moulded from a flexible rubber composition and here shown of flattened tapered form having a central passage 2 which is accessible through a smaller opening 3 either moulded or cut in the convergent end of the body for the reception of the lead-in wires 4.

The inner end face 5 of the plug body is finished in a flat plane and provided with a diagonal slit or slot 6 in register with the central passage 2, forming overhanging lugs I, the undersides of which are'sloped from the respective side walls of the passage 2 diagonally of the axis thereof as indicated at 8 so that when the leadin wires are inserted through the passage 2 they will be deflected through the slot 6 to be readily grasped.

Pockets 9 lead inwardly from the face 5 on opposite sides of the central passage 2 and the sides of the pockets adjacent the edge of the plug body slope angularly inward from the face 5 as indicated at Hi to meet rectangular sockets H which extend a substantial depth parallel with the axis of passage 2.

The inner walls I2 of the sockets II are provided with socket recesses i3 and one side wall of each of said recesses is raised above the bottom 9 of the pockets 9 and sloped in substantial right angular relation to the respective surface ill to provide positioning stop abutments l4 hereinafter referred to.

A raised shoulder l5-is positioned at the outward sides of the sloping abutments [4 within the pockets 9 for positioning contact with the edges of the terminals hereinafter referred to.

Upon reference to Figures 7 and 8, the special formation of the insert terminal prongs IE will be apparent. Each terminal comprises a strip of metal having a prong end I! and the other end I8 is disposed in a plane parallelly oifset from the plane of disposition of the prong l1 and the intermediate portion of the metal strip has a part It angularly inclined to engage the sloping surface III of the plug body in positioning and supporting contact and the adjacent part ll extends in substantial right-angular relation to the portion l8 so that the undersurface thereof rests in supported positioning contact with the correspondingly sloped stop abutments I4, while the edge portion of the angular part IT engages the side surface of the adjacent shoulder 15 in positioning contact.

This relationship between the insert terminals, and the plug body is achieved when the por tions i8 are pressed into the sockets II and it will be noted that the portions l8 have a locking lug l8" pressed outwardly therefrom in a wedgelike manner and these lugs embed themselves in the flexible material of the plug body and efiectively lock the terminals against accidental withdrawal, but at the same time permit ready insertion of the terminals.

In addition to the supporting contacts above referred to presented by the surfaces 10, l4 and I5, the sides of the overhanging lugs I are also surfaced at I to engage the flat inner face of the terminals and also at 'I" to engage the adjacent edge of the terminals.

The portions I1 have the terminal screws l'l threaded thereinto and these are of a suflicient length to facilitate the placing of the ends of the lead-in wires thereabout after they have been bent about the edges of the terminals at the ends of the diagonal slot 6. The fact that the terminal screws are angularly related to the terminal prongs l1, provides the desired clearance between the heads of the screws and the prongs to facilitate placing of the wires, while at the same. time providing a compact assembly. The inner ends of the terminal screws II' are accommodated within the pocket recesses i3.

The resilient nature of the plug body will permit the walls of the slots 8 to be distorted or spread apart to facilitate entry or manipulation of the. terminal wires and this may even be made in the form of a slit, so that when the wires are-once in position the resiliency of the plug material will retain the slit in its constricted form.

It will be understood however that the invention is not restricted to the use of a rubber composition in the manufacture of the plug body, since other mouldable compositions may be employed while retaining essential features of the invention.

What I claim as my invention is:

1. An attachment plug of the type having a resilient body moulded with terminal-receiving sockets on either side of a central wire terminal passage and terminal prongs inserted in said sockets, characterized in that said body is formed with mating integral wedge-shaped lugs projecting in opposite directions in register with said central passage at one end thereof with their adjacent overlapping edges parallelly tapered to form a slot diagonally intersecting a plane which plane intersects the said terminal prongs centrally and longitudinally, to direct the terminal wires respectively to the opposite outer sides of said terminal-receiving sockets to,

facilitate connection with the minal prongs.

2. An attachment plug of the type comprising a resilient body and terminals recessed into the plug body from one end and presenting prong projections therebeyond, characterized in that said terminals each comprises a single thickness strip of metal bent intermediate of its length to present an obtuse angular portion and a supporting portion therebeyond substantially rightangularly related to the obtuse portion, said latter portion terminating in an anchoring extension obtusely related to said latter portion and offset parallelly from the projecting prong portion, said resilient body being formed to present supporting and positioning contact with said first-mentioned obtuse portions of the terrespective ter-.

minals and with the inner end of the said pro-' jecting prong portions, and a terminal screw threaded into the first-mentioned obtuse portion of each terminal.

LEWIS J. CLAYTON. 

